if you're getting a blister from housework only when your wife goes away, you're not doing enough of it !
but seriously, i could be wrong but i've heard that the type of battery used in these devices actually works better if you don't let it run down completely, and "top it up" regularly.
there have been a few threads around on the topic, you might find them if you do a search for "battery charge" or something. alternately, someone who knows more about the technical side might come along and explain it better than i can...
but, in three words, i wouldn't worry.
as for the reading blister... you know, you have to start off slow and follow a serious training regime when you get a liseuse ! it's like cycling, you can't ride the Tour de France the week after you get a bicycle ! i would say, start off with 15 minute training sessions. then move to 30 minutes. then soon you can read for 1 hour. be sure to drink plenty of water while you're training, eat light and get plenty of rest. and don't forget special gear : besides the obvious good reading light, you might want to invest in a helmet to avoid brain strain from too much reading, and some gloves to protect your thumb...
